1. Field of the Invention
The present invention relates to a metal melting apparatus and a method for melting metal that preheat metal granules or metal sheets with heat from the metal melting apparatus before heating and melting the granular metals or sheet metals.
2. Description of the Prior Art(s)
A conventional method for melting metal is to put metal materials, such as metal ingots, metal lumps, metal scraps and the like, into a furnace to heat the metal materials until they are melted. When the metal materials are melted into liquid and mixed, the molten metal materials are further injected into mold cavities of molds to form specific shapes.
However, before the metal materials, especially the metal ingots and the metal lumps, are put into the furnace to be heated, the metal materials are at an ordinary temperature so that melting the metal materials takes a long time. Moreover, since the temperature of the molten materials is very high, ladling the molten materials out of the furnace should be done very carefully no matter by manual or by automatic means in case accident happens. Furthermore, when ladling the molten materials, processes of heating and melting the metal materials have to stop. Operators are not able to go on putting the metal materials into the furnace until the molten materials are all injected into the mold cavities of the molds. Therefore, the conventional method for melting metal is disfluent, time consuming and laborious.
To overcome the shortcomings, the present invention provides a metal melting apparatus and a method for melting metal to mitigate or obviate the aforementioned problems.